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		<a class="header-logo header-affix-hide margin-left-no margin-right-no" data-offset-top="213" data-spy="affix">串珠子</a>
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                串珠子                </h1>
                <p>时间限制：10s&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;  空间限制：128MB</p>			</div>
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                                <h3>题目描述</h3><p><p></p>
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<div class="pdcont" style="font-size: 12pt; color: rgb(32,0,0); font-family: 'Times New Roman', 宋体"></div>
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<p><span id="1324814811462E" style="display: none">&nbsp;</span></p>
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<div class="pdcont" style="font-size: 12pt; color: rgb(32,0,0); font-family: 'Times New Roman', 宋体">　　铭铭有n个十分漂亮的珠子和若干根颜色不同的绳子。现在铭铭想用绳子把所有的珠子连接成一个整体。<br />
　　现在已知所有珠子互不相同，用整数1到n编号。对于第i个珠子和第j个珠子，可以选择不用绳子连接，或者在ci,j根不同颜色的绳子中选择一根将它们连接。如果把珠子看作点，把绳子看作边，将所有珠子连成一个整体即为所有点构成一个连通图。特别地，珠子不能和自己连接。<br />
　　铭铭希望知道总共有多少种不同的方案将所有珠子连成一个整体。由于答案可能很大，因此只需输出答案对1000000007取模的结果。<br />
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<div class="pdcont" style="font-size: 12pt; color: rgb(32,0,0); font-family: 'Times New Roman', 宋体">　</div></p><hr/><h3>输入格式</h3><p><p><span style="font-size: medium">　标准输入。输入第一行包含一个正整数n，表示珠子的个数。接下来n行，每行包含n个非负整数，用空格隔开。这n行中，第i行第j个数为ci,j。<br />
</span></p>
<div class="pdcont" style="font-size: 12pt; color: rgb(32,0,0); font-family: 'Times New Roman', 宋体"><span style="font-size: medium">　</span></div></p><hr/><h3>输出格式</h3><p><p><span style="font-size: medium">　标准输出。输出一行一个整数，为连接方案数对1000000007取模的结果。<br />
</span></p></p><hr/><h3>样例输入</h3><pre>3
0 2 3
2 0 4
3 4 0

</pre><hr/><h3>样例输出</h3><pre>50</pre><hr/><h3>提示</h3><p><p>　　对于100%的数据，n为正整数，所有的ci,j为非负整数且不超过1000000007。保证ci,j=cj,i。每组数据的n值如下表所示。<br />
&nbsp;<br />
编号&nbsp;1&nbsp;2&nbsp;3&nbsp;4&nbsp;5&nbsp;6&nbsp;7&nbsp;8&nbsp;9&nbsp;10&nbsp;&nbsp;&nbsp; <br />
n&nbsp;&nbsp;&nbsp;&nbsp; &nbsp;8&nbsp;9&nbsp;9&nbsp;10&nbsp;11&nbsp;12&nbsp;13&nbsp;14&nbsp;15&nbsp;16&nbsp; <br />
</p></p><hr/><h3>题目来源</h3><p>2012国家集训队Round 1 day1</p>
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